This article lists the professional tennis players who reached the highest ranking among their compatriots during the Open Era. The rankings used are ATP rankings for men (since 23 August 1973 for singles, and 1 March 1976 for doubles) and WTA rankings for women (since 3 November 1975 for singles, and 4 September 1984 for doubles).
On 11 September 2017, Garbiñe Muguruza and Rafael Nadal made Spain the first country since the United States 14 years ago to simultaneously top both the ATP and the WTA rankings, with Muguruza making her debut in the No. 1 spot. The most recent previous such pair were Serena Williams and Andre Agassi, 28 April to 11 May 2003.
Top ranked by country – singles
Men
Women
* Monica Seles is included twice due to change of citizenship.
Most successful by country in an Open Era Grand Slam – singles
Men
Oceania
Australia: Champion (x15) Rod Laver 1968 Wimbledon, 1969 Australian Open, 1969 French Open, 1969 Wimbledon, 1969 US Open John Newcombe 1970 Wimbledon, 1971 Wimbledon, 1973 Australian Open, 1973 US Open, 1975 Australian Open Ken Rosewall 1968 French Open, 1970 US Open, 1971 Australian Open, 1972 Australian Open Patrick Rafter 1997 US Open, 1998 US Open Lleyton Hewitt 2001 US Open, 2002 Wimbledon Mark Edmondson 1976 Australian Open Pat Cash 1987 Wimbledon New Zealand: Finalist Onny Parun 1973 Australian Open Chris Lewis 1983 Wimbledon
North America
Bahamas: Third Round
Roger Smith
1994 US Open
Barbados: First Round
Darian King
2017 US Open
Canada: Finalist
Milos Raonic
2016 Wimbledon
Costa Rica
Dominican Republic: Third Round
Víctor Estrella Burgos
2014 US Open
El Salvador
Guatemala
Haiti: Fourth Round
Ronald Agénor
1988 US Open
Jamaica: Third Round (x2) Dustin Brown 2013 Wimbledon, 2015 Wimbledon Mexico: Semifinalist (x3) Raúl Ramírez 1976 French Open, 1976 Wimbledon, 1977 French Open United States: Champion (x51) Pete Sampras 1990 US Open, 1993 Wimbledon, 1993 US Open, 1994 Australian Open, 1994 Wimbledon, 1995 Wimbledon, 1995 US Open, 1996 US Open, 1997 Australian Open, 1997 Wimbledon, 1998 Wimbledon, 1999 Wimbledon, 2000 Wimbledon, 2002 US Open Jimmy Connors 1974 Australian Open, 1974 Wimbledon, 1974 US Open, 1976 US Open, 1978 US Open, 1982 Wimbledon, 1982 US Open, 1983 US Open Andre Agassi 1992 Wimbledon, 1994 US Open, 1995 Australian Open, 1999 French Open, 1999 US Open, 2000 Australian Open, 2001 Australian Open, 2003 Australian Open John McEnroe 1979 US Open, 1980 US Open, 1981 Wimbledon, 1981 US Open, 1983 Wimbledon, 1984 Wimbledon, 1984 US Open Jim Courier 1991 French Open, 1992 Australian Open, 1992 French Open, 1993 Australian Open Arthur Ashe US Open, 1970 Australian Open, 1975 Wimbledon Stan Smith 1971 US Open, 1972 Wimbledon Roscoe Tanner 1977 Australian Open (January) Vitas Gerulaitis 1977 Australian Open (December) Johan Kriek 1982 Australian Open Michael Chang 1989 French Open Andy Roddick 2003 US Open
South America
Argentina: Champion (x6) Guillermo Vilas 1977 French Open, 1977 US Open, 1978 Australian Open, 1979 Australian Open Gastón Gaudio 2004 French Open Juan Martin del Potro 2009 US Open Bolivia: Third Round Mario Martinez 1983 French Open Brazil: Champion (x3) Gustavo Kuerten 1997 French Open, 2000 French Open, 2001 French Open Chile: Finalist Marcelo Ríos 1998 Australian Open Fernando González 2007 Australian Open Colombia: Fourth Round Daniel Elahi Galan 2023 Wimbledon Ecuador: Champion Andrés Gómez 1990 French Open Paraguay: Finalist Víctor Pecci 1979 French Open Peru: Quarterfinalist (x2) Jaime Yzaga 1991 Australian Open, 1994 US Open Uruguay: Quarterfinalist Marcelo Filippini 1999 French Open Venezuela: Third Round Nicolás Pereira 1995 US Open
Africa
Algeria: First Round
Lamine Ouahab
2009 Australian Open
Egypt: Quarterfinalist
Ismail El Shafei
1974 Wimbledon
Kenya: Second Round
Paul Wekesa
1989 Australian Open
Morocco: Quarterfinalist (x4) Younes El Aynaoui 2000 Australian Open, 2002 US Open, 2003 Australian Open, 2003 US Open Nigeria: Fourth Round Nduka Odizor 1983 Wimbledon Senegal: First Round (x4) Yahiya Doumbia 1988 French Open, 1988 Wimbledon, 1988 US Open, 1989 US Open South Africa: Champion Johan Kriek 1981 Australian Open Tunisia: Third Round (x2) Malek Jaziri 2015 Australian Open, 2017 Australian Open Zimbabwe: Quarterfinalist (x2) Byron Black 1995 US Open, 2000 Wimbledon